Yes, that is my feeling about it, too - that morale or happiness would not be about population control. Population control is better tied to a different set of of factors.
But approval and morale do have the potential to be useful in deepening the game experience in a wide array of areas. (And for that matter, morale and approval should be two separate things. A population might really love their leader but are could still be low in morale). These things could impact production (low morale means lower work rates). It could impact wealth accumulation (if in concept, wealth is generated by taxes, the lower the approval... the more people become tax evaders!) Approval could be affected by all sorts of things like war, peace, or whatever.
Anyway, I do hope it will be added in some way to create a new layer of depth. *crosses fingers*